New SPECT camera is faster, clearer than conventional SPECT imaging

BOSTON—New high-speed SPECT technology provides objective quantitative measures of myocardial perfusion and function, compared to conventional SPECT imaging at up to one-seventh the acquisition time, according to data presented during the late breaking clinical trial sessions on Sept. 13 at the American Society of Nuclear Cardiology (ASNC) conference.

Researchers said that a new high-speed SPECT camera (D-SPECT, Spectrum Dynamics), employing cadmium zinc telluride crystal arrays, has been shown in single-center studies to detect a similar amount of myocardial perfusion abnormality compared to a conventional SPECT camera (Anger or A-SPECT, Siemens Healthcare) in up to one-seventh the acquisition time.

Tali Sharir, MD, from Procardia Maccabi Healthcare Services in Tel Aviv, Israel, and colleagues compared the quantitative results of myocardial perfusion and function by the high-speed SPECT to the conventional SPECT in a prospective, multicenter trial.

The investigators performed D-SPECT myocardial perfusion imaging (MPI) within 30 minutes of A-SPECT. The rest/stress acquisition times were 20 and 15 minutes, respectively for A-SPECT, and four and two minutes, respectively for D-SPECT.

They then analyzed perfusion using QPS software, deriving the total perfusion defect (TPD) of stress and rest, expressing overall extent and severity of perfusion defects.

According to the researchers, D-SPECT stress and rest TPD in the entire cohort correlated linearly to A-SPECT TPD over a wide range of perfusion abnormality. High linear correlation between D-SPECT and A-SPECT stress TPD was seen at each of the participating centers.

Sharir and colleagues found that normalcy rate in 61 patients with low prescan likelihood of coronary artery disease were 95.1 percent and 90.2 percent for D-SPECT and A-SPECT, respectively. They also found that the post-stress ejection fraction (EF), end-diastolic volume and end-systolic volume by D-SPECT correlated linearly to A-SPECT over a wide range of EF and volumes.